Experimental and theoretical study on the reaction Sc+NO -> ScO+N

Abstract

The Sc + NO --> ScO + N exo-ergic reaction has been studied both experimentally and theoretically. A beam-gas experiment with continuous wave (cw) laser-induced fluorescence characterization of the ScO product has been carried out to determine the rotational distribution in the X (2)Sigma(+)(nu = 0) state. It is very close to a Prior statistical distribution, indicating the probable existence of a long-lived intermediate complex. The relevant potential energy surfaces have been calculated by ab initio quantum chemical methods. Two isomers for the stable intermediate, ScNO, have been found which can be symbolized as NScO (obtuse N-Sc-O angle) and Sc[NO] (acute N-Sc-O angle). Some features of the collision mechanism are discussed, and a more accurate value for the bond energy of ScO is deduced to be 6.92 +/- 0.01 eV. We also show that the harpooning model does not apply to the title reaction.